Mold for freezing ice cubes



R. B. BRINDLEY Filed Oct. 23, 1965 MOLD FOR FREEZING ICE CUBES 3,280,588 MOLD FOR FREEZING ICE CUBES Richard B. Brindiey, La Crosse, Wis., assignor to La Crosse Cooler Company, La Crosse,l Wis., a corporation of Wisconsin Filed st. 23, 1965, Ser. No. 503,589 Claims. (Cl. 62-340) This invention relates to a mold for freezing ice cubes.

The evaporator mold is particularly designed for use in a Vcycle in which the mold is alternately heat absorbing and heat rejecting. In accordance with conventional practice in molds of this type, an evaporator tube or other heat exchanger is bonded to the base of the mold. By means with which the present application is not concerned, it delivers refrigerant into the tube in heat absorbing relation to the mold during a part of the cycle to freeze ice cubes in the mold and then delivers hot fluid through the tube in heat yconductive relation to the mold during another part of the cycle to release the ice cubes from adhesion to the mold for discharge therefrom.

In devices of this kind, the mold is commonly closed or nearly closed at its top and is entirely open at its bottom, water being introduced either by immersing the mold to lill its several pockets, or by spraying the water into the pockets where it freezes immediately on Contact, or by providing a temporary bottom for the mold which serves as a closure for supporting the water until it freezes. Sin-ce the mold comprises a plurality of inten connecting partitions to form the pockets in which the ice cubes are frozen, it has been a common problem in the prior art devices of this character to prevent the ice cubes from having frozen integral connection with each other across the partitions, thus precluding them from dropping freely and individually from the mold when the latter is heated.

The present invention solves this problem by forming the partitions from a laminate which has a highly thermally conductive metal exposed to the Water and the ice cubes frozen therefrom, each partition comprising plies of such metal spaced by a ply of relatively heat insulating material such as synthetic resin (preferably with suitable non-metallic filler). The thermal insulation provided by the core of each partition prevents the Water from freezing across the partition from one pocket to the next While, at the same time, the external metallic plies conduct heat to and from the contents. For example, heat is conducted simultaneously to all surfaces of the ice cubes formed in the respective pockets so that all of them will be discharged substantially concurrently during that part of the cycle in which the mold is exposed to heat.

In the drawings:

FIG. 1 is a fragmentary view in plan of a portion of an evaporator-mold embodying the invention.

FIG. 2 is a fragmentary side elevation of one of the partitions involved.

FIG. 3 is a fragmentary side elevation of a partition complementary to that of FIG. 2 to extend transverse with respect thereto.

FIG. 4 is a plan view of the partition shown in FIG. 2.

FIG. 5 is an exploded perspective view fragmentarily iilustrating the component parts of the mold in mutually separated positions.

FIG. 6 is a fragmentary detail View showing a portion of the assembled mold as it appears in perspective when inverted.

To facilitate gravity discharge of the ice cubes, the mold as illustrated to exemplify the present invention is of a type which is inverted as compared with the conventional household ice cube tray.

The evaporator tubes 8 are bonded to a base wall 10 States Patent O Lil which `constitutes the top of the mold. The tubes 8 are connected together in series by tubular headers 12 at the ends of the base plate 10. Tubes 8 extend forth and back across the wall 10.

Extending transversely of the under side of plate 10 are partitions 14 provided at intervals with notches 16 for interlocking engagement with the complementary notches 18 of the longitudinal partitions 20. The Ilatter have tongues 22 which extend through the slots 24 with which the base plate 10 is provided. When the grid of partitions 14 and 20 is assembled to the face plate 10, the partitions are lmaintained in association with each other and with the base plate by solder or the like to provide a unitary structure in which a series of ice cube molding cells 30 are produced. These open downwardly. FIG. 6 shows the assembly in inverted position, the solder being diagrammatically illustrated at 26.

It is a feature of the present invention that each of these several partitions 14 and 20 is a laminar strip having a non-metallic thermally insulating core and metallic face plies which are highly heat conductive. The core is conveniently made of a synthetic resin, care being used to employ a material Which is odorless land does not impart taste to the water or other liquid frozen therein. The resin may be either thermosetting or thermoplastic materiai having low heat conductivity. It may be reinforced or non-reinforced. An epoxy resin reinforced with woven glass fiber has been 4found to be appropriate. In practice, the resin core is laminated with light gauge metal (two ounce copper being an example) on both faces to make a sheet about one-sixteenth of an inch thick, more or less, from which the .partition strips are sheared. FIGS. 4 and 6 diagrammatically illustrate the thermally insulating plastic core 32 and the thermally conductive metal face plies 34. It will be observed that the core ply 32 is exposed between the metal plies along the edge 36 of each of the four sides `of each of the ice freezing pockets 3i).

In use, the face plies 34, being bonded by soldering or the like to each other and to the base plate 10, place the contents of the pocket in direct thermally conductive relation to the base plate and the tubes 8. In the refrigerating cycle yfreezing progresses so rapidly as to be substantially instantaneous upon contact of the unfrozen liquid with these surfaces or with the ice previously formed.

However, since there is no metallic contact across the edges 36 of the partition walls 30, there will be no tendency for the liquid to freeze across these walls to provide continuity of ice from one pocket to another.

When the refrigeration cycle is reversed and relatively warm Huid traverses the evaporator tubes S, the heat passes directly through the base plate 1) and the surface plies 34 of the laminated partition to provide sufficient melting to free the ice cubes from the partitions thereby permitting the immediate discharge of the ice cubes by gravity or otherwise from the respective pockets 30.

In practice, the base plate 10 has conducted the heat effectively when made of 14 gauge copper. To facilitate release of the cubes, the pockets are vented through the small ports 38. It Will, of course, be understood that details are supplied by way of example and not by way of limitation.

I claim:

1. A m-old for freezing ice cubes, said mold comprising a base having heat exchange passages in unitary connection therewith, and a series of ice cube molding pockets for which the base provides closures land which comprise intersecting partitions bonded to each other and to the base and having laminar wall portions each comprising a non-metallic core ply of thermally non-conductive ma- 3 terial and face plies comprising highly heat conductive metal.

2. A mold according to claim 1 in which the said Wall portions have edges remote fromfsaid base at Which the core ply is exposed.

3. A mold according to claim 1 in which certain of said wall portions have tongues engaged in slots with which the base is provided.

4. A mold for freezing ice cubes, said mold comprising a base having heat exchange passages in unitary connection therewith, and a series -of ice cube molding pockets mounted on the base andl having laminar longitudinal and transverse wall portions each comprising a non-.metallic core ply 'of thermally non-conductive material and face plies comprising highly heat conductive metal, the face plies having a heat-conductive metallic bond to said base and to the face plies of other wall portions.

5. In a device for making ice cubes, an evaporator mold comprising a base plate, a series of evaporator tubes bonded to the base plate and extending forth and back across the base plate, a set of complementarily notched partition strips mounted on and depending from the base plate and in interlocking engagement with each other and forming cellular pockets Within which ice cubes can be molded, Aeach of said strips having metallic face plies of highly conductive metalfbonded to each other and to the base plate and each of said strips having a non-metallic ply of thermally insulating material as a core betweenl sai-d face plies and exposed at the margins of the respective strips which are remote from the base plate.

References` Cited by the Examiner UNITED STATES PATENTS 2,508,625 5/1950 Smith 62347 X 3,009,336 1l/196l Bayston et al. 62-347 X 3,171,267 3/1965 Mitchell 62-348 X ROBERT A. OLEARY, Primary Examiner,

W. E. WAYNER, Assistant Examiner. 

1. A MOLD FOR FREEZING ICE CUBES, SAID MOLD COMPRISING A BASE HAVING HEAT EXCHANGE PASSAGES IN UNITARY CONNECTION THEREWITH, AND A SERIES OF ICE CUBE MOLDING POCKETS FOR WHICH THE BASE PROVIDES CLOSURES AND WHICH COMPRISE INTERSECTING PARTITIONS BONDED TO EACH OTHER AND TO THE BASE AND HAVING LAMINAR WALL PORTIONS EACH COMPRISING A NON-METALLIC CORE PLY OF THERMALLY NON-CONDUCTIVE MATERIAL AND FACE PLIES COMPRISING HIGHLY HEAT CONDUCTIVE METAL. 